This present description relates to medical ultrasound imaging. In particular, parametric imaging for rotational motion of the heart is provided with ultrasound imaging.
Ultrasound is used to assist in diagnosis of heart conditions. Doppler velocity and/or B-mode imaging of the heart provides real-time images of the heart. Two or three dimensional images are viewed as static images or dynamic clips. However, other analysis or characteristics may be derived from ultrasound information, such as strain or strain rate.
In “Strain And Strain Rate Parametric Imaging. A New Method For Post Processing Three Standard Apical Planes To 3-/4-Dimensional Images. Preliminary Data On Feasibility, Artefact And Regional Dyssynergy Visualization,” Støylen et al. describe off-line visualization for heart diagnosis. In U.S. Application Publication No. 2005/0288589, parametric imaging of the heart is derived from ultrasound information. Dynamic clips or videos of the parametric imaging provide temporally useful information to a user. The parametric imaging may include values determined from data at different locations or different times, such as strain or tissue tracking values. The parametric values may be derived from heart cycle phase information. The ultrasound data may be responsive to contrast agents. The ultrasound data may be acquired with a three-dimensional scan or a plurality of two-dimensional scans.
Tissue tracking with ultrasound data may provide some rotational information. Data for a single, two-dimensional plane is acquired of a short axis view of the left ventricle of the heart. Tissue tracking with the data determines the circumferential motion. In magnetic resonance imaging, the torsion of the heart may be calculated. However, the torsion has insufficient temporal resolution for clinical utility.